---
layout: docs
page_title: Vault HSM support overview
description: >-
  Review how HSM support in Vault works with external root key storage and
  automatic unsealing.
---

> [!IMPORTANT]  
> **Documentation Update:** Product documentation, which were located in this repository under `/website`, are now located in [`hashicorp/web-unified-docs`](https://github.com/hashicorp/web-unified-docs), colocated with all other product documentation. Contributions to this content should be done in the `web-unified-docs` repo, and not this one. Changes made to `/website` content in this repo will not be reflected on the developer.hashicorp.com website.

# Vault HSM support overview

@include 'alerts/enterprise-only.mdx'

- Root key Wrapping: Vault protects its root key by transiting it through
  the HSM for encryption rather than splitting into key shares
- Automatic Unsealing: Vault stores its HSM-wrapped root key in storage,
  allowing for automatic unsealing
- [Seal Wrapping](/vault/docs/enterprise/sealwrap) to provide FIPS
  KeyStorage-conforming functionality for Critical Security Parameters
- [Entropy Augmentation](/vault/docs/enterprise/entropy-augmentation) to
  allow Vault to sample entropy from an external cryptographic module.

HSM support is available for devices that support PKCS#11 version 2.20+
interfaces and provide integration libraries, and is currently available for
linux/amd64 platforms only. It has successfully been tested against many
different vendor HSMs; HSMs that provide only subsets of the full PKCS#11
specification can usually be supported but it depends on available
cryptographic mechanisms.

Please note however that configuration details, flags, and supported features
within PKCS#11 vary depending on HSM model and configuration. Consult your
HSM's documentation for more details.

Some parts of Vault work differently when using an HSM. Please see the
[Behavioral Changes](/vault/docs/enterprise/hsm/behavior) page for
important information on these differences.

The [Configuration](/vault/docs/configuration/seal/pkcs11) page contains
configuration information.

The [Security](/vault/docs/enterprise/hsm/security) page contains
information about deploying Vault's HSM support in a secure fashion.

Finally, the [HSM partners](/vault/docs/partners/hsm) page contains
information about HashiCorp partner products that have been verified to work with Vault 
for Auto Unsealing / HSM Support and External Key Management.
